US5599731A - Method of forming a field oxide film in a semiconductor device - Google Patents
Method of forming a field oxide film in a semiconductor device Download PDFInfo
- Publication number
- US5599731A US5599731A US08/498,914 US49891495A US5599731A US 5599731 A US5599731 A US 5599731A US 49891495 A US49891495 A US 49891495A US 5599731 A US5599731 A US 5599731A
- Authority
- US
- United States
- Prior art keywords
- forming
- oxide film
- film
- pad
- field oxide
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 238000000034 method Methods 0.000 title claims abstract description 17
- 239000004065 semiconductor Substances 0.000 title claims abstract description 9
- 229910021420 polycrystalline silicon Inorganic materials 0.000 claims abstract description 16
- 229920005591 polysilicon Polymers 0.000 claims abstract description 16
- 150000004767 nitrides Chemical class 0.000 claims abstract description 15
- 238000007254 oxidation reaction Methods 0.000 claims abstract description 13
- 230000002265 prevention Effects 0.000 claims abstract description 9
- 238000000059 patterning Methods 0.000 claims abstract description 5
- 229920002120 photoresistant polymer Polymers 0.000 claims description 9
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 6
- 229910052710 silicon Inorganic materials 0.000 claims description 6
- 239000010703 silicon Substances 0.000 claims description 6
- 239000000758 substrate Substances 0.000 claims description 6
- 239000007789 gas Substances 0.000 claims description 4
- 230000003647 oxidation Effects 0.000 claims 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N nitrogen Substances N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims 2
- 229910052757 nitrogen Inorganic materials 0.000 claims 2
- -1 nitrogen ions Chemical class 0.000 claims 2
- 239000007943 implant Substances 0.000 claims 1
- 239000012535 impurity Substances 0.000 claims 1
- 150000002500 ions Chemical class 0.000 claims 1
- 241000293849 Cordylanthus Species 0.000 abstract description 7
- 125000004433 nitrogen atom Chemical group N* 0.000 abstract description 7
- 210000003323 beak Anatomy 0.000 abstract 1
- 238000005530 etching Methods 0.000 description 2
- 238000005468 ion implantation Methods 0.000 description 2
- 125000004429 atom Chemical group 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000002513 implantation Methods 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
- H01L21/31—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to form insulating layers thereon, e.g. for masking or by using photolithographic techniques; After treatment of these layers; Selection of materials for these layers
- H01L21/32—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to form insulating layers thereon, e.g. for masking or by using photolithographic techniques; After treatment of these layers; Selection of materials for these layers using masks
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
- H01L21/31—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to form insulating layers thereon, e.g. for masking or by using photolithographic techniques; After treatment of these layers; Selection of materials for these layers
Definitions
- the present invention relates to a method of forming a field oxide film in a semiconductor device, and more particularly, to a method of forming a field oxide film in a semiconductor device which can minimize an occurrence of a bird's beak by forming a pad polysilicon film between a nitride film and a pad oxide film, defining field regions by patterning the nitride film, and forming an oxidization prevention layer by implanting nitrogen atoms into portions where the bird's beak will occur.
- a field oxide film is formed to isolate semiconductor elements.
- FIG. 1 is a sectional view of a semiconductor device for explaining a method of forming a field oxide film according to the prior art.
- a field oxide film 5 is formed by patterning a nitride film 3 and the pad oxide film 2 to define a field region after forming a pad oxide film 2 and a nitride film 3 on a silicon substrate 1, and by forming a channel stop region 4 on the silicon substrate 1 by an ion implantation process.
- the present invention discloses a method of forming a field oxide film, comprising steps of:
- a pad oxide film, a pad polysilicon film, and a nitride film on a silicon substrate sequentially forming a pad oxide film, a pad polysilicon film, and a nitride film on a silicon substrate; forming a channel stop region after patterning the nitride film to define a field region; forming a photoresist pattern on a selected portion of the exposed pad polysilicon film, and thereafter, forming an oxidization prevention layer by implanting nitrogen atoms into the pad polysilicon film exposed at the edge of the photoresist pattern; and performing a thermal oxidization process after removing the photoresist pattern, and forming a field oxide film by removing the nitride film, pad polysilicon film, and pad oxide film.
- FIG. 1 is a sectional view for explaining a method of forming a field oxide film according to the prior art.
- FIGS. 2A through 2E are sectional views for illustrating steps of forming a field oxide film in a semiconductor device of the present invention.
- a pad oxide film 12, a pad polysilicon film 13, and a nitride film 14 are sequentially formed on a silicon substrate 11.
- the pad polysilicon film 13 is exposed by excessively etching the nitride film 14 by an etching process utilizing an isolation mask to define a field region, and thereafter, a channel stop region 15 is formed on the silicon substrate 11 by an ion-implantation process.
- a photoresist pattern 16 is formed on a selected portion of the exposed pad polysilicon film 13, and thereafter, nitrogen atoms are ion-implanted to the pad polysilicon film 13 exposed at the edge of the photoresist pattern 16 under the condition of 10 to 30 KeV and 1 ⁇ 10 12 -1 ⁇ 10 15 atoms/cm 2 .
- the nitrogen atoms are ion-implanted into the pad polysilicon film 13, which acts as an oxidization prevention area 17 during a thermal oxidization process.
- NH 2 and NO gas can be used instead of the nitrogen atoms to form the oxidization prevention area 17.
- the photoresist pattern 16 is removed, and thereafter, a field oxide film 18 having a predetermined thickness is formed by the thermal oxidization process. Therefore, the bird's beak does not occur due to the oxidization prevention area 17 which is formed by the implantation of any member of the group consisting of nitrogen atoms, NH 2 gas, and NO gas.
- the field oxide film 18 is completed by removing the remaining nitride film 14, pad polysilicon film 13 and pad oxide film 12.
- the present invention improves yield and reliability by preventing the occurrence of the bird's beak using the oxidization prevention layer.
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Manufacturing & Machinery (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Local Oxidation Of Silicon (AREA)
- Element Separation (AREA)
Abstract
The present invention discloses a method of forming a field oxide film in a semiconductor device which can minimize an occurrence of a birds beak by forming a pad polysilicon film between a nitride film and a pad oxide film, defining field regions by patterning the nitride film, and forming an oxidization prevention layer by implanting nitrogen atoms into portions where the bird's beak will otherwise occur.
Description
1. Field of the Invention
The present invention relates to a method of forming a field oxide film in a semiconductor device, and more particularly, to a method of forming a field oxide film in a semiconductor device which can minimize an occurrence of a bird's beak by forming a pad polysilicon film between a nitride film and a pad oxide film, defining field regions by patterning the nitride film, and forming an oxidization prevention layer by implanting nitrogen atoms into portions where the bird's beak will occur.
2. Information Disclosure Statement
In general, a field oxide film is formed to isolate semiconductor elements.
FIG. 1 is a sectional view of a semiconductor device for explaining a method of forming a field oxide film according to the prior art. Referring to FIG. 1, a field oxide film 5 is formed by patterning a nitride film 3 and the pad oxide film 2 to define a field region after forming a pad oxide film 2 and a nitride film 3 on a silicon substrate 1, and by forming a channel stop region 4 on the silicon substrate 1 by an ion implantation process.
As a bird's beak B is formed from an edge of the field oxide film 5 to an active region at the time of forming the field oxide film 5, the active region is reduced, causing a great obstacle in the manufacturing of a highly integrated device.
Therefore, it is an object of the present invention to provide a method of forming a field oxide film in a semiconductor device which can improve the yield and reliability of the device by preventing the occurrence of the bird's beak in the active region.
The present invention discloses a method of forming a field oxide film, comprising steps of:
sequentially forming a pad oxide film, a pad polysilicon film, and a nitride film on a silicon substrate; forming a channel stop region after patterning the nitride film to define a field region; forming a photoresist pattern on a selected portion of the exposed pad polysilicon film, and thereafter, forming an oxidization prevention layer by implanting nitrogen atoms into the pad polysilicon film exposed at the edge of the photoresist pattern; and performing a thermal oxidization process after removing the photoresist pattern, and forming a field oxide film by removing the nitride film, pad polysilicon film, and pad oxide film.
For a full understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in conjunction with the accompanying drawings in which:
FIG. 1 is a sectional view for explaining a method of forming a field oxide film according to the prior art.
FIGS. 2A through 2E are sectional views for illustrating steps of forming a field oxide film in a semiconductor device of the present invention.
Similar reference characters refer to similar parts through the accompanying drawings.
Referring to FIG. 2A, a pad oxide film 12, a pad polysilicon film 13, and a nitride film 14 are sequentially formed on a silicon substrate 11.
Referring to FIG. 2B, the pad polysilicon film 13 is exposed by excessively etching the nitride film 14 by an etching process utilizing an isolation mask to define a field region, and thereafter, a channel stop region 15 is formed on the silicon substrate 11 by an ion-implantation process.
Referring to FIG. 2C, a photoresist pattern 16 is formed on a selected portion of the exposed pad polysilicon film 13, and thereafter, nitrogen atoms are ion-implanted to the pad polysilicon film 13 exposed at the edge of the photoresist pattern 16 under the condition of 10 to 30 KeV and 1×1012 -1×1015 atoms/cm2.
The nitrogen atoms are ion-implanted into the pad polysilicon film 13, which acts as an oxidization prevention area 17 during a thermal oxidization process. With either of NH2 and NO gas can be used instead of the nitrogen atoms to form the oxidization prevention area 17.
Referring to FIG. 2D, the photoresist pattern 16 is removed, and thereafter, a field oxide film 18 having a predetermined thickness is formed by the thermal oxidization process. Therefore, the bird's beak does not occur due to the oxidization prevention area 17 which is formed by the implantation of any member of the group consisting of nitrogen atoms, NH2 gas, and NO gas.
Referring to FIG. 2E, the field oxide film 18 is completed by removing the remaining nitride film 14, pad polysilicon film 13 and pad oxide film 12.
As described above, the present invention improves yield and reliability by preventing the occurrence of the bird's beak using the oxidization prevention layer.
Although this invention has been described in its preferred embodiment with a certain degree of particularity, one skilled in the art to which this invention pertains would know that the preferred embodiment disclosed here is only an example and that the construction, combination, and arrangement of its parts may be varied without departing from the spirit and the scope of the invention.
Claims (2)
1. A method of forming a semiconductor device, comprising:
sequentially forming a pad oxide film, a pad polysilicon film, and a nitride film on a silicon substrate;
implanting impurity ions to form a channel stop region after patterning said nitride film to define a field region;
exposing a selected portion of said exposed pad polysilicon by forming a photoresist pattern;
forming an oxidation prevention area by implanting nitrogen ions into said selected portion of said pad polysilicon film exposed at an edge of said photoresist pattern;
removing said photoresist pattern and subsequently performing a thermal oxidation process; and
forming a field oxide film by removing said nitride film, said pad polysilicon film, and said pad oxide film.
2. The method as in claim 1, wherein said implanting comprises using NH2 or NO gas to implant nitrogen ions to form said oxidation prevention area.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR94-16087 | 1994-07-06 | ||
| KR1019940016087A KR960005839A (en) | 1994-07-06 | 1994-07-06 | Field oxide film formation method of a semiconductor device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US5599731A true US5599731A (en) | 1997-02-04 |
Family
ID=19387332
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US08/498,914 Expired - Fee Related US5599731A (en) | 1994-07-06 | 1995-07-06 | Method of forming a field oxide film in a semiconductor device |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US5599731A (en) |
| KR (1) | KR960005839A (en) |
| CN (1) | CN1108637C (en) |
| GB (1) | GB2291260B (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5830790A (en) * | 1994-02-24 | 1998-11-03 | Samsung Electronics Co., Ltd. | High voltage transistor of semiconductor memory devices |
| US5972777A (en) * | 1997-07-23 | 1999-10-26 | Taiwan Semiconductor Manufacturing Company, Ltd. | Method of forming isolation by nitrogen implant to reduce bird's beak |
| US5972746A (en) * | 1996-10-08 | 1999-10-26 | Mosel Vitelic, Inc. | Method for manufacturing semiconductor devices using double-charged implantation |
| US5994190A (en) * | 1995-12-18 | 1999-11-30 | Nec Corporation | Semiconductor device with impurity layer as channel stopper immediately under silicon oxide film |
| US6001709A (en) * | 1997-12-19 | 1999-12-14 | Nanya Technology Corporation | Modified LOCOS isolation process for semiconductor devices |
| US6015736A (en) * | 1997-12-19 | 2000-01-18 | Advanced Micro Devices, Inc. | Method and system for gate stack reoxidation control |
| US6025240A (en) * | 1997-12-18 | 2000-02-15 | Advanced Micro Devices, Inc. | Method and system for using a spacer to offset implant damage and reduce lateral diffusion in flash memory devices |
| US6194288B1 (en) | 1999-01-04 | 2001-02-27 | Taiwan Semiconductor Manufacturing Company | Implant N2 into a pad oxide film to mask the active region and grow field oxide without Si3N4 film |
| US6353253B2 (en) * | 1996-05-02 | 2002-03-05 | Advanced Micro Devices, Inc. | Semiconductor isolation region bounded by a trench and covered with an oxide to improve planarization |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101359615B (en) * | 2007-07-30 | 2010-08-11 | 中芯国际集成电路制造(上海)有限公司 | Semiconductor isolation structure and manufacturing method of semiconductor device |
| CN104299984A (en) * | 2013-07-19 | 2015-01-21 | 北大方正集团有限公司 | Semiconductor device and manufacture method thereof |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5791536A (en) * | 1980-11-29 | 1982-06-07 | Toshiba Corp | Semiconductor device and manufacture thereof |
| US4407696A (en) * | 1982-12-27 | 1983-10-04 | Mostek Corporation | Fabrication of isolation oxidation for MOS circuit |
| JPS6171646A (en) * | 1984-09-17 | 1986-04-12 | Oki Electric Ind Co Ltd | Manufacture of semiconductor device |
| JPH01297837A (en) * | 1988-05-25 | 1989-11-30 | Sony Corp | Manufacture of semiconductor device |
| JPH05144805A (en) * | 1991-11-22 | 1993-06-11 | Mitsubishi Electric Corp | Manufacture of semiconductor device |
| US5308787A (en) * | 1993-10-22 | 1994-05-03 | United Microelectronics Corporation | Uniform field oxidation for locos isolation |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0020144B1 (en) * | 1979-05-31 | 1986-01-29 | Fujitsu Limited | Method of producing a semiconductor device |
| US5149669A (en) * | 1987-03-06 | 1992-09-22 | Seiko Instruments Inc. | Method of forming an isolation region in a semiconductor device |
| US5192707A (en) * | 1991-07-31 | 1993-03-09 | Sgs-Thomson Microelectronics, Inc. | Method of forming isolated regions of oxide |
-
1994
- 1994-07-06 KR KR1019940016087A patent/KR960005839A/en not_active Application Discontinuation
-
1995
- 1995-06-29 GB GB9513225A patent/GB2291260B/en not_active Expired - Fee Related
- 1995-07-06 CN CN95108397A patent/CN1108637C/en not_active Expired - Fee Related
- 1995-07-06 US US08/498,914 patent/US5599731A/en not_active Expired - Fee Related
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5791536A (en) * | 1980-11-29 | 1982-06-07 | Toshiba Corp | Semiconductor device and manufacture thereof |
| US4407696A (en) * | 1982-12-27 | 1983-10-04 | Mostek Corporation | Fabrication of isolation oxidation for MOS circuit |
| JPS6171646A (en) * | 1984-09-17 | 1986-04-12 | Oki Electric Ind Co Ltd | Manufacture of semiconductor device |
| JPH01297837A (en) * | 1988-05-25 | 1989-11-30 | Sony Corp | Manufacture of semiconductor device |
| JPH05144805A (en) * | 1991-11-22 | 1993-06-11 | Mitsubishi Electric Corp | Manufacture of semiconductor device |
| US5308787A (en) * | 1993-10-22 | 1994-05-03 | United Microelectronics Corporation | Uniform field oxidation for locos isolation |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5830790A (en) * | 1994-02-24 | 1998-11-03 | Samsung Electronics Co., Ltd. | High voltage transistor of semiconductor memory devices |
| US5994190A (en) * | 1995-12-18 | 1999-11-30 | Nec Corporation | Semiconductor device with impurity layer as channel stopper immediately under silicon oxide film |
| US6353253B2 (en) * | 1996-05-02 | 2002-03-05 | Advanced Micro Devices, Inc. | Semiconductor isolation region bounded by a trench and covered with an oxide to improve planarization |
| US5972746A (en) * | 1996-10-08 | 1999-10-26 | Mosel Vitelic, Inc. | Method for manufacturing semiconductor devices using double-charged implantation |
| US5972777A (en) * | 1997-07-23 | 1999-10-26 | Taiwan Semiconductor Manufacturing Company, Ltd. | Method of forming isolation by nitrogen implant to reduce bird's beak |
| US6025240A (en) * | 1997-12-18 | 2000-02-15 | Advanced Micro Devices, Inc. | Method and system for using a spacer to offset implant damage and reduce lateral diffusion in flash memory devices |
| US6001709A (en) * | 1997-12-19 | 1999-12-14 | Nanya Technology Corporation | Modified LOCOS isolation process for semiconductor devices |
| US6015736A (en) * | 1997-12-19 | 2000-01-18 | Advanced Micro Devices, Inc. | Method and system for gate stack reoxidation control |
| US6194288B1 (en) | 1999-01-04 | 2001-02-27 | Taiwan Semiconductor Manufacturing Company | Implant N2 into a pad oxide film to mask the active region and grow field oxide without Si3N4 film |
Also Published As
| Publication number | Publication date |
|---|---|
| GB9513225D0 (en) | 1995-09-06 |
| KR960005839A (en) | 1996-02-23 |
| GB2291260A (en) | 1996-01-17 |
| GB2291260B (en) | 1997-08-13 |
| CN1133490A (en) | 1996-10-16 |
| CN1108637C (en) | 2003-05-14 |
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Legal Events
| Date | Code | Title | Description |
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| AS | Assignment |
Owner name: HYUNDAI ELECTRONICS INDUSTRIES CO., LTD., KOREA, R Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:PARK, SANG HOON;REEL/FRAME:007647/0042 Effective date: 19950616 |
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| STCH | Information on status: patent discontinuation |
Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 |
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| FP | Lapsed due to failure to pay maintenance fee |
Effective date: 20090204 |